Followup on c058562d73
Before this commit, Domain for `purchase_ok` on the field `product_id` was applied on the field level which was Replaced by multi-company domain on views.
With this commit, we combine both domains to Display only `Can be Purchased` products.
closes odoo/odoo#47778
X-original-commit: 842b8a383b7868a89cbd3d81b0065cce37606db4
Signed-off-by: Simon Lejeune (sle) <sle@openerp.com>